string prgFilePath = System.Environment.GetFolderPath(Environment.SpecialFolder.CommonProgramFiles);
string stsadmPath = prgFilePath + @"\Microsoft Shared\web server extensions\12\BIN\stsadm.exe";
System.Diagnostics.Process proc = new System.Diagnostics.Process();
//Wait for the end of the process
proc.EnableRaisingEvents = false;
proc.StartInfo.FileName = stsadmPath;
proc.StartInfo.Arguments = "-o setproperty -url http://dcmoss:50020/ -pn "peoplepicker-nowindowsaccountsfornonwindowsauthenticationmode" -pv yes";
proc.Start();
//Wait
proc.WaitForExit();
With this method you can dynamically activate or deactivate feature, make some maintenance operation, change properties...